I have no idea why this is happening. At first I believed it was a one-off thing based on Google Panda. Now I am really unsure? The activity level on the site has dropped a lot, it is pretty "dead" with a handful of active users. Everyone else spends their time in Facebook or Twitter.
I am not an expert at SEO or Traffic. If someone can take a look at my site I would be grateful. I know that I made a few changes with add-ons, and there are URL redirects happening also.
Please PM me for more info and if you can help advise.